I love my new C-7 but some of my best runs are destroyed by hitting cones with the right rear of the car. I am thinking about a Go Pro with suction cup so I can figure out how to get close without the penalty.
E-Bay has lots of used units for under $100. My car has PDR so I don't need an expensive unit.
1) Do all GP's include a strong suction cup?
2) Do all units download to a PC?

They do not include a suction cup, they all do download to PC by either plugging the camera in to the PC via micro usb cable or removing the micro usb card and placing it into a card reader. Some of the newer ones have WiFi capability where you can wirelessly transfer files to iPad or pc.

Amazon has has several strong suction cup mounts available. I have one that has held stron on the side of the car at 150mph. Also, there are several cameras out there that take quality video for a cheap entry point. Knock off gopros I would call them and some of them are pretty decent.

Yes GoPros connect to pc/Mac no problems at all. No they don’t come with a suction cup as the others have stated. I use a RAM mount which are top notch and American made but not the cheapest. I have only mounted mine inside the car on the rear hatch glass so i cant speak to how well it holds up in the wind. However, the HPDE events I run require you to have the camera tethered somehow if you are using an exterior mount so it doesn’t become a track hazard if it comes off. I don’t see this being as big of a hazard on an autocross course but you still may want to double check if they require it to be tethered when mounted externally.

just dont do what i did! miss the cones with the car, only to hit one with the go pro suction mount!
(was on front fender behind tire, shooting the tire and forward, obviously lower than the height of a cone. )

I run the GoPro suction mount for events. It's BIG so it's got a lot of surface area to grab. I put it on my B pillar behind me so I can see my hands and forward.
I'd highly suggest not going too cheap on it with a knock off Chinese brand if possible.

You don't need to waste money for that GOPRO just for the purpose to see how close you are. Just get more seat time and hand buff those cone marks off. You'll stop hitting those cones or buff your clear coat off.

Gopro is a very good tool to improve your driving skill if other competitors post their runs after the event so you can make a good comparison. Gopro 6 is my 3rd Gopro. The very first Gopro came with the suction cup but the latest ones don't. I got one of those cheap ebay suction cup and it looks identical to what came with the original Gopro and working fine.

My PDR works well to review my run right after my first run. However, I can't really tell where my car is relative to a cone. You can connect your phone to the recent Gopro and review your previous runs while you are competing.

I mount it on my roof and remote start with my phone. The issue is that it drains the battery really quickly but fine for 4 or 5 runs.